A mobile X-ray apparatus can be moved inside and outside a medical facility, and is capable of taking an X-ray. The mobile X-ray apparatus takes an X-ray using power stored in an internal battery. For this reason, a user is required to charge a battery in advance before using the mobile X-ray apparatus. PTL 1 discloses a mobile X-ray apparatus which switches to a chargeable state if a battery residual capacity is lower than the amount of power required to take an X-ray, and notifies a user that the battery residual capacity is low (refer to PTL 1).